Grain Dust Explosions--An Unsolved Problem
HRD-79-1: Published: Mar 21, 1979. Publicly Released: Mar 21, 1979.
- Full Report:
Of all the industrial dust explosions in the United States, those in grain elevators cause the most injuries and property damage. Between December 1977 and January 1978, several grain dust explosions occurred, killing 62 persons and injuring 53. Although the conditions that contribute to explosions are well known, the causes of most grain explosions are not known. Thus, a grain elevator operator could use many methods to prevent explosions without assurance of success. It has been suggested that grain dust, especially the finer dust collected by control systems, should not be reintroduced to the grain; however, the effectiveness of this method for reducing the possibility of an explosion has not been proven.
The Department of Labor's Occupational Safety and Health Administration (OSHA) is authorized to develop and enforce occupational safety and health regulations, but the it has not adopted or developed standards specifically designed for grain elevators. Labor's grain elevator inspections have increased in number and appear to have improved in quality. More emphasis has been placed on the factors that cause explosions and fires, such as ignition sources and dust accumulations. Although Labor's standards deal with many hazards that could cause explosions, there is no assurance that compliance with present standards would prevent explosions. Labor has contracted with the National Academy of Sciences to determine whether existing standards are adequate. Although grain dust poses certain health hazards, Labor appears to be giving limited emphasis to such hazards.
Recommendation for Executive Action
Comments: Please call 202/512-6100 for additional information.
Recommendation: The Department of Labor should: (1) make timely and thorough investigations of future grain explosions using explosion experts and require comparable investigations of any explosions at locations where Labor has given enforcement authority to the states; (2) have safety inspectors do health sampling for dust during grain elevator inspections; and (3) expand the scope of its contract with the National Academy of Sciences to provide enough time for a more thorough study that would include an evaluation of the causes of grain dust explosions and the adequacy of the OSHA standards. The Department of Health, Education, and Welfare should modify its proposed contract with the National Academy of Sciences to provide that the Committee on Evaluation of Industrial Hazards thoroughly consider potential methods of reducing grain explosions, including dust control and explosion venting.